Removal of lead and other suspended solids from used hydrocarbon lubricating oil

摘要

Lead and other dispersed solids present in used hydrocarbon lubricating oil which also contains water and light hydrocarbon impurities are removed by a process wherein agglomeration of the suspended lead and other solids is induced by heat treatment of the used oil at about 500 to 700 DEG F after flashing off the water and light hydrocarbon material. The agglomerated solids are readily separated from the heat treated oil by conventional physical separation techniques such as centrifuging or gravity settling to afford a used oil substantially free, i.e., at least 90% lead removal, of lead and other solid contaminants.